SUB-ELEMENT E

Question 1

What is the voltage range considered to be valid logic low input in a TTL device operating at 5 volts?
A. 2.0 to 5.5 volts.
B. -2.0 to -5.5 volts.
C. Zero to 0.8 volts.
D. 5.2 to 34.8 volts.

Answer 1

C

Question 2

What is the voltage range considered to be a valid logic high input in a TTL device operating at 5.0 volts?
A. 2.0 to 5.5 volts.
B. 1.5 to 3.0 volts.
C. 1.0 to 1.5 volts.
D. 5.2 to 34.8 volts.

Answer 2

A

Question 3

What is the common power supply voltage for TTL series integrated circuits?
A. 12 volts.
B. 13.6 volts.
C. 1 volt.
D. 5 volts.

Answer 3

D

Question 4

TTL inputs left open develop what logic state?
A. A high-logic state.
B. A low-logic state.
C. Open inputs on a TTL device are ignored.
D. Random high- and low-logic states.

Answer 4

A

Question 5

Which of the following instruments would be best for checking a TTL logic circuit?
A. VOM.
B. DMM.
C. Continuity tester.
D. Logic probe.

Answer 5

D

Question 6

What do the initials TTL stand for?
A. Resistor-transistor logic.
B. Transistor-transistor logic.
C. Diode-transistor logic.
D. Emitter-coupled logic.

Answer 6

B

Question 7

What is a characteristic of an AND gate?
A. Produces a logic “0” at its output only if all inputs are logic “1”.
B. Produces a logic “1” at its output only if all inputs are logic “1”.
C. Produces a logic “1” at its output if only one input is a logic “1”.
D. Produces a logic “1” at its output if all inputs are logic “0”.

Answer 7

B

Question 8

What is a characteristic of a NAND gate?
A. Produces a logic “0” at its output only when all inputs are logic “0”.
B. Produces a logic “1” at its output only when all inputs are logic “1”.
C. Produces a logic “0” at its output if some but not all of its inputs are logic “1”.
D. Produces a logic “0” at its output only when all inputs are logic “1”.

Answer 8

D

Question 9

What is a characteristic of an OR gate?
A. Produces a logic “1” at its output if any input is logic “1”.
B. Produces a logic “0” at its output if any input is logic “1”.
C. Produces a logic “0” at its output if all inputs are logic “1”.
D. Produces a logic “1” at its output if all inputs are logic “0”.

Answer 9

A

Question 10

What is a characteristic of a NOR gate?
A. Produces a logic “0” at its output only if all inputs are logic “0”.
B. Produces a logic “1” at its output only if all inputs are logic “1”.
C. Produces a logic “0” at its output if any or all inputs are logic “1”.
D. Produces a logic “1” at its output if some but not all of its inputs are logic “1”.

Answer 10

C

Question 11

What is a characteristic of a NOT gate?
A. Does not allow data transmission when its input is high.
B. Produces a logic “0” at its output when the input is logic “1” and vice versa.
C. Allows data transmission only when its input is high.
D. Produces a logic “1” at its output when the input is logic “1” and vice versa.

Answer 11

B

Question 12

Which of the following logic gates will provide an active high out when both inputs are active high?
A. NAND.
B. NOR.
C. AND.
D. XOR.

Answer 12

C

Question 13

In a negative-logic circuit, what level is used to represent a logic 0?
A. Low level. C. Negative-transition level.
B. Positive-transition level. D. High level.

Answer 13

D

Question 14

For the logic input levels shown in Figure 3E12, what are the logic levels of test points A, B and C in this circuit? (Assume positive logic.)
A. A is high, B is low and C is low.
B. A is low, B is high and C is high.
C. A is high, B is high and C is low.
D. A is low, B is high and C is low.

Answer 14

B

Question 15

For the logic input levels given in Figure 3E13, what are the logic levels of test points A, B and C in this circuit? (Assume positive logic.)
A. A is low, B is low and C is high.
B. A is low, B is high and C is low.
C. A is high, B is high and C is high.
D. A is high, B is low and C is low.

Answer 15

C

Question 16

In a positive-logic circuit, what level is used to represent a logic 1?
A. High level
B. Low level
C. Positive-transition level
D. Negative-transition level

Answer 16

A

Question 17

Given the input levels shown in Figure 3E14 and assuming positive logic devices, what would the output be?
A. A is low, B is high and C is high. C. A is low, B is low and C is high.
B. A is high, B is high and C is low. D. None of the above are correct.

Answer 17

A

Question 18

What is a truth table?
A. A list of input combinations and their corresponding outputs that characterizes a digital device’s function.
B. A table of logic symbols that indicate the high logic states of an op-amp.
C. A diagram showing logic states when the digital device’s output is true.
D. A table of logic symbols that indicates the low logic states of an op-amp.

Answer 18

A

Question 19

A flip-flop circuit is a binary logic element with how many stable states?
A. 1
B. 2
C. 4
D. 8

Answer 19

B

Question 20

What is a flip-flop circuit? A binary sequential logic element with ___stable states.
A. 1
B. 4
C. 2
D. 8

Answer 20

C

Question 21

How many flip-flops are required to divide a signal frequency by 4?
A. 1
B. 4
C. 8
D. 2

Answer 21

D

Question 22

How many bits of information can be stored in a single flip-flop circuit?
A. 1
B. 2
C. 3
D. 4

Answer 22

A

Question 23

How many R-S flip-flops would be required to construct an 8 bit storage register?
A. 2
B. 4
C. 8
D. 16

Answer 23

C

Question 24

An R-S flip-flop is capable of doing all of the following except:
A. Accept data input into R-S inputs with CLK initiated.
B. Accept data input into PRE and CLR inputs without CLK being initiated.
C. Refuse to accept synchronous data if asynchronous data is being input at same time.
D. Operate in toggle mode with R-S inputs held constant and CLK initiated.

Answer 24

D

Question 25

The frequency of an AC signal can be divided electronically by what type of digital circuit? A. Free-running multivibrator. B. Bistable multivibrator. C. OR gate. D. Astable multivibrator.

Answer 25

B

Question 26

What is an astable multivibrator? A. A circuit that alternates between two stable states. B. A circuit that alternates between a stable state and an unstable state. C. A circuit set to block either a 0 pulse or a 1 pulse and pass the other. D. A circuit that alternates between two unstable states.

Answer 26

D

Question 27

What is a monostable multivibrator? A. A circuit that can be switched momentarily to the opposite binary state and then returns after a set time to its original state. B. A “clock” circuit that produces a continuous square wave oscillating between 1 and 0. C. A circuit designed to store one bit of data in either the 0 or the 1 configuration. D. A circuit that maintains a constant output voltage, regardless of variations in the input voltage.

Answer 27

A

Question 28

What is a bistable multivibrator circuit commonly named? A. AND gate. B. OR gate. C. Clock. D. Flip-flop.

Answer 28

D

Question 29

What is a bistable multivibrator circuit? A. Flip-flop. B. AND gate. C. OR gate. D. Clock.

Answer 29

A

Question 30

What wave form would appear on the voltage outputs at the collectors of an astable, multivibrator, common-emitter stage? A. Sine wave. B. Sawtooth wave. C. Square wave. D. Half-wave pulses.

Answer 30

C

Question 31

What is the name of the semiconductor memory IC whose digital data can be written or read, and whose memory word address can be accessed randomly? A. ROM – Read-Only Memory. B. PROM – Programmable Read-Only Memory. C. RAM – Random-Access Memory. D. EPROM – Electrically Programmable Read-Only Memory.

Answer 31

C

Question 32

What is the name of the semiconductor IC that has a fixed pattern of digital data stored in its memory matrix? A. RAM – Random-Access Memory. B. ROM – Read-Only Memory. C. Register. D. Latch.

Answer 32

B

Question 33

What does the term “IO” mean within a microprocessor system? A. Integrated oscillator. B. Integer operation. C. Input-output. D Internal operation.

Answer 33

C

Question 34

What is the name for a microprocessor’s sequence of commands and instructions? A. Program. B. Sequence. C. Data string. D. Data execution.

Answer 34

A

Question 35

How many individual memory cells would be contained in a memory IC that has 4 data bus input/output pins and 4 address pins for connection to the address bus? A. 8 B. 16 C. 32 D. 64

Answer 35

D

Question 36

What is the name of the random-accessed semiconductor memory IC that must be refreshed periodically to maintain reliable data storage in its memory matrix? A. ROM – Read-Only Memory. B. DRAM – Dynamic Random-Access Memory. C. PROM – Programmable Read-Only Memory. D. PRAM – Programmable Random-Access Memory.

Answer 36

B

Question 37

In a microprocessor-controlled two-way radio, a “watchdog” timer: A. Verifies that the microprocessor is executing the program. B. Assures that the transmission is exactly on frequency. C. Prevents the transmitter from exceeding allowed power out. D. Connects to the system RADAR presentation.

Answer 37

A

Question 38

What does the term “DAC” refer to in a microprocessor circuit? A. Dynamic access controller. B. Digital to analog converter. C. Digital access counter. D. Dial analog control.

Answer 38

B

Question 39

Which of the following is not part of a MCU processor? A. RAM B. ROM C. I/O D. Voltage Regulator

Answer 39

D

Question 40

What portion of a microprocessor circuit is the pulse generator? A. Clock B. RAM C. ROM D. PLL

Answer 40

A

Question 41

In a microprocessor, what is the meaning of the term “ALU”? A. Automatic lock/unlock. B. Arithmetical logic unit. C. Auto latch undo. D. Answer local unit.

Answer 41

B

Question 42

What circuit interconnects the microprocessor with the memory and input/output system? A. Control logic bus. B. PLL line. C. Data bus line. D. Directional coupler.

Answer 42

C

Question 43

What is the purpose of a prescaler circuit? A. Converts the output of a JK flip-flop to that of an RS flip-flop. B. Multiplies an HF signal so a low-frequency counter can display the operating frequency. C. Prevents oscillation in a low frequency counter circuit. D. Divides an HF signal so that a low-frequency counter can display the operating frequency.

Answer 43

D

Question 44

What does the term “BCD” mean? A. Binaural coded digit. B. Bit count decimal. C. Binary coded decimal. D. Broad course digit.

Answer 44

C

Question 45

What is the function of a decade counter digital IC? A. Decode a decimal number for display on a seven-segment LED display. B. Produce one output pulse for every ten input pulses. C. Produce ten output pulses for every input pulse. D. Add two decimal numbers.

Answer 45

B

Question 46

What integrated circuit device converts an analog signal to a digital signal? A. DAC B. DCC C. ADC D. CDC

Answer 46

C

Question 47

What integrated circuit device converts digital signals to analog signals? A. ADC B. DCC C. CDC D. DAC

Answer 47

D

Question 48

In binary numbers, how would you note the quantity TWO? A. 0010 B. 0002 C. 2000 D. 0020

Answer 48

A